The present invention relates generally to a Venetian blind cutting machine, and more particularly to a clamping device of the Venetian blind cutting machine, which is capable of clamping the slats of the Venetian blind automatically.
In early years, the cutting proceeding of the Venetian blind was carried out by a cutting machine, which can only cut the head rail, the bottom rail and the slats of the Venetian blind one by one. Recently, there are cutting machines, which can cut the elements of the Venetian blind in a single procedure. In the prior arts, the Venetian blind cutting machine provided a mold, which provided receiving holes for clamping the head rail, the bottom rail and the slats therein. Then a cutter, which is driven by motor or hydraulic linear actuator, cuts them into the end items.
U.S. Pat. No. 6,079,306 disclosed a Venetian blind cutting machine, which comprises a mold having top-rail block, a bottom-rail block and a slat block. The top-rail block and the bottom-rail block have receiving holes for clamping head rail and bottom rail therein. The bottom-rail block slides toward or away from the slat block for receiving slats in the space between the two blocks. A bolt is to drive the bottom-rail block slides pressing the slats, such that a cutter can cut the slats in a predetermined length. After that, operator can loosen the bolt to take the slats out.
Many Venetian blind cutting machines in the market are similar to the prior art as disclosed above. Each of these cutting machines usually has a sliding block (such as the bottom-rail block disclosed in the U.S. Pat. No. 6,079,306) for pressing the slats. A clamping device (such as the bolt disclosed in the U.S. Pat. No. 6,079,306) is to push the sliding block for clamping the slats as described above. Then a cutter is driven to cutter the slats. After cut-off the elements, the clamping device also can draw the sliding block back for taking the slats out.
Another apparatus for clamping slats in a conventional Venetian blind cutting machine is to dispose a base block beside the mold. A threaded rod is screwed into the base block and having inner end thereof orientating to the sliding block. The outer end of the thread rod provides with a crank for operator to grip it to turn for driving the threaded rod shifting forward to press the sliding block for clamping the slats.
In operating the prior arts as described above, operator must drive the sliding block to clamp the slats and to release the slats in every cut-off procedure. It is not a fine operating procedure.
The primary objective of the invention is to provide a clamping apparatus of Venetian blind cutting machine, which can automatically lock and release the slats.
According to the objective of the invention, a Venetian blind cutting machine of the present invention comprising a mold assembly, which has a main block and a guiding slot on the main block. A sliding block slidably receives in the guiding slot. The guiding slot has at least one stopping portion for stopping the sliding block. The sliding slot is for receiving slats therein between a closed end of the guiding slot and the sliding block. A cutter is slidably provided at the main block of the mold assembly for free shifting. At least one driving bar has one end thereof fastening to the cutter. The driving bar is substantially parallel to the guiding slot and being driven to shift along the guiding slot, and a joint block has at least one opening for receiving the driving bar and holding the driving bar therein by friction. The joint block is fastened to the sliding block of the mold assembly. Whereby, the driving bar will drive the cutter, the joint block and the sliding block to move along with it. The sliding block will press the slats first to lock the slats in the guiding slot automatically. While the joint block has been pressing the slats, the driving force of the driving bar will overcome the friction of the joint block. Thus, the joint block will loosen the driving bar and the driving bar will move continually and drive the cutter to cut the slats.